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1.
中医认为,秋燥之气最易伤肺。因为肺脏直接与大气相通,且与皮肤和大肠有密切的关系。冷空气到来后,最容易刺激呼吸系统,加上抵抗力减弱,就给病原微生物以可乘之机,极  相似文献   

2.
孙旭 《植物杂志》2011,(2):54-55
中医认为,秋燥之气最易伤肺。因为肺脏直接与大气相通,且与皮肤和大肠有密切的关系。冷空气到来后,最容易刺激呼吸系统,加上抵抗力减弱,就给病原微生物以可乘之机,极易使人伤风感冒。而进入冬季后,寒冷的天气让人们更愿意生活在室内。  相似文献   

3.
要研究大气污染对植物的影响,人工熏气试验装置是不可缺少的手段。最早采用的设备是静态式人工熏气罩,即在密闭的小室中一次通入(或在罩内直接发生)高浓度的污染气体,以观察各种植物的反应。这种装置由于不能控制稳定的气体浓度,罩内环境条件与外界自然情况相差极大,目前已很少为国内外所应用。比较进步的是动态式人工熏气小室,即使小室中保持与外界相通的空气流,随气流加入一定浓度的污染气体。这种装置能够控制恒定  相似文献   

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植物体内的有机物运输是当前植物生理学研究中十分活跃的一个领域。本文拟着重以有机物的胞间运转、向韧皮部的装卸及其在筛管中纵向迁移的机理为主,作一些简要的介绍。高等植物是一个共质体和质外体相互交叉,互为依存的统一体由胞壁、细胞间隙构成的自由空间遍及植物全身、相互连续。水、气、溶质充斥其中,与外界直接相通,进行自由的物质交换;维管束中的管胞、导管是自由空间分化、发展的高级形式。  相似文献   

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目的:探讨胎儿重复肾畸形的超声诊断的图像特征及误诊原因。方法:回顾分析我院30例经产前超声诊断为重复肾胎儿的超声图像及其临床资料。结果:30例重复肾胎儿中,出生后经手术或临床证实或终止妊娠后经解剖证实的共有27例,出生后经复查双肾正常的胎儿共有3例。27例重复肾胎儿中,单侧、双侧重复肾分别占22、5例,共32侧重复肾,其中合并输尿管扩张、合并输尿管囊肿的分别占14、4侧;合并其他系统气管畸形的胎儿共6侧,其中染色体三体综合征的有4例;出现4例误诊;胎儿重复肾声像图特征:1呈囊肿样改变肾上极占4侧,类圆形无回声区,壁较薄、光滑,与输尿管相通;2肾窦区可见两个不相通的肾盂,分离肾盂占11侧,未与输尿管相通;3肾窦区可见两个不相通肾盂,分离肾盂占14侧,上肾盂或下肾盂相连于输尿管;4 3侧肾窦区见两个不分离的肾盂,肾脏形态拉长,未与输尿管相通。结论:胎儿重复肾的超声声像图特征主要为两个不相通的肾盂;加强在胎儿中晚孕期时做常规多切面扫查,有利于提高对重复肾胎儿的确诊精确率,为临床评估胎儿提供借鉴。  相似文献   

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发掘维罗纳气单胞菌特异性更强的检测靶点和毒力相关基因靶点,建立能够检测致病性维罗纳气单胞菌的PCR检测方法.通过序列比对分析气单胞菌的16S rRNA基因序列,筛选对维罗纳气单胞菌特异的引物,用于检测种特异性,利用气单胞菌气溶素基因保守引物,检测菌株的致病性,并进行反应条件和反应体系的优化,灵敏度试验和特异性试验.发掘并设计的维罗纳气单胞菌16S rRNA特异性引物结合气单胞菌气溶素基因保守引物建立的检测方法,对12株气单胞菌和10株非气单胞菌的检测结果显示,所有致病性维罗纳气单胞菌都能扩增到大小分别为343 bp和232 bp的特异性条带,而非维罗纳气单胞菌的致病性气单胞菌只能扩增到232 bp的气溶素基因特异性条带,其它菌株都不能扩增到目的条带.灵敏度试验表明,该反应体系的检测灵敏度为1.35×10-3 mg/L.我们建立的致病性维罗纳气单胞菌检测方法能特异地检测致病性维罗纳气单胞菌,并具有高度灵敏性.  相似文献   

7.
<正>2021年4月,我有幸参加了由中国人与生物圈专家委员会组织的海南热带雨林国家公园考察。五指山、鹦哥岭、尖峰岭、霸王岭、吊罗山,一路下来大森林清凉的山风涤荡了我30多年从事红树林工作积淀下来的一身咸水味,倍感精神气爽。置身崇山峻岭,遥对远方的大海,每每思绪万千。在我的印象中“纠缠”指相隔遥远的两个基本粒子之间说不清道不明的诡秘互动,它们虽然从未谋面却能心心相通。在生态系统的宏观层次,海南滨海红树林跟内陆热带雨林之间是否也存在一定程度的纠缠?哪怕这一纠缠是间接的,长时间尺度上的演化关系。  相似文献   

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八脉交会穴,又称流注八穴、交经八穴等,是四肢上与奇经八脉脉气相通的八个穴位,首见于《针经指南.标幽赋》:"阳跷阳维并督脉,主肩背腰腿在表之病;阴跷阴维任带冲,去心腹胁肋在里之疑"。八脉交会穴应用很广,由于奇经与正经的经气以此八穴相通,所以此八穴既能治奇经病,又能治正经病,李梴在《医学入门》中说:"八法者,奇经八穴为要,乃十二经之大会也,周身三百六十穴,统于手足六十六穴,六十六穴又统于八穴。"中医学中并没有"小儿脑性瘫痪"这个病名,但根据临床表现属于"五迟""五软"的范畴,多缘于先天禀赋不足,肝肾亏虚,加之后天调护失宜,痰浊内生,瘀血内停,致脏腑经络功能失常,气血运行不畅,筋骨失养,髓海失充,所以主要临床表现为运动障碍和异常姿势,并常伴有健康和体力障碍、智能和情绪问题、语言障碍、癫痫、听力障碍、视觉障碍、牙齿发育不良及行为障碍等。要讲八脉交会穴在脑瘫治疗中的应用,就必然要先谈奇经八脉与八脉交会穴的的关系。  相似文献   

9.
草履虫的采集和简易培养方法   总被引:1,自引:0,他引:1  
一、采集方法在一般水池中都能采到,但在有机质丰富、略有臭味的死水沟、水坑中(如与稻田、苇塘相通的有机质丰富的小水洼、与食堂相通的下水道、污水井中)最多。如在水坑内放上几把稻草,或从水田中采些稻茬和水草带回,取其中下部剪成小段,放入清水中,在20℃左右的条件下,培养10天左右也可看到较多的草履虫(用此法也可培养变形虫)。  相似文献   

10.
自然环境中广泛存在各种微生物,在正常人体的表面,以及与外界相通的腔道中也存在着一定种类与数量的微生物.即使出生前处于无菌环境中的胎儿,在出生经过产道时,皮肤也会被微生物污染.出生后开始吞咽和呼吸,此时外界微生物即随之进入呼吸道及肠道.所以人的皮肤、粘膜及与外界相通的口腔、鼻咽腔、肠道、泌尿生殖道等均有微生物的存在.这些微生物绝大部分为细菌.在体表存在的细菌有:  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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